1. Field of the Invention
The present invention relates to container closures having a capability for spreading contents of the container and, more particularly, to a container closure having a cap and a brush formed as a single unitary member, and to a method of forming a one-piece cap and brush.
2. Prior Art
Various types of container closures suitable for sealing container contents against leakage and having a brush secured thereto for spreading container contents are known. Substances such as rubber cement, certain types of ink, correction fluid for covering typing errors, and the like are particularly useful when the caps which seal their containers carry brushes for distributing the substances.
Most prior proposals for cap and brush assemblies have called for the stem of the brush to be formed as a part which is separate from the cap. Forming a brush stem separately from a cap and then assembling these parts as by gluing, welding, pressing or other known connection techniques have added significantly to the cost of cap and brush assemblies. Another problem associated with two-piece cap and stem structures has been the tendency of the stem to separate from the cap when the stem and brush are being pulled out of a bottle wherein the liquid contained within the bottle has set-up slightly or otherwise increased in viscosity.
The referenced Plural-Part Cap Assembly Case discloses such a two-piece arrangement. While the type of connection disclosed therein represents a significant advance in providing a cap and brush assembly with a secure connection between a cap and a brush stem, the cost of separately forming cap and brush stem components, and the cost of assembling these components in accordance with this proposal is still higher than desired.
To the degree that proposals have been made for forming a cap and an elongate applicator as an integral structure, the types of structures which have been proposed have been suitable for formation only with an unscrewing type mold which includes a complex assembly of parts for threading a molded cap and applicator structure off of the mold once the molded structure has been formed. Limitations imposed on the configurations of such structures as can be molded where there is a need to unscrew the resulting molded structures from the mold have not permitted a desirable type of integral cap and applicator to be formed. Moreover, unscrewing-type molds are undesirable from the viewpoint of their excessively high cost.
3. The Cap and Brush Assembly Case
The referenced Cap and Brush Assembly Case relates to a one-piece cap and brush stem construction to which brush bristles are secured in order to complete the formation of a cap and brush assembly. The one-piece cap and brush stem structure assures that the brush stem does not separate from the remainder of the cap, as is commonplace with many two-piece cap and brush stem assemblies. At the time the invention of the Cap and Brush Assembly Patent was conceived, it was not appreciated that brush bristles could be formed integrally with a one-piece cap and stem structure.